The PI proposes a high-impact collaborative research project to identify the most prevalent multimorbidity combinations; develop an understanding of the typical sequence of disease progression for each multimorbidity combination; and assess the incremental costs associated with each progression. The Center for Health Care Strategies calls for developing the means to identify homogeneous multimorbidity subgroups to more effectively develop targeted interventions. This work will support the National Institute on Aging 21st Century strategic directions for research on aging especially goals (E and F) related to understanding health differences, health disparities and developing strategies for intervention and policy decisions. Through completing the study's three aims, we will significantly improve scientific knowledge. A lack of emphasis on multimorbidities can have a significant negative impact on care. Factoring in multimorbidity should better explain healthcare expenditures. Understanding the typical disease progression sequence for each multimorbidity combination has the potential to assist with estimating the future healthcare burden and understand relationships between different diseases. The process of formulating interventions to treat and prevent combinations of comorbid diseases can be made simpler, less costly, more reliable and repeatable, more personalized, and more productive. To our knowledge, no research has attempted to identify all common multimorbidity patterns in a population of this size using a similar method, nor identified progression patterns at this scale. Further, greater insight into multimorbidities combinations is essential to further aging research as a significant proportion of the trend in multimorbidity is attributable to aging. Additionally, the research project we propose will allow us to expand our compute cluster, which is accessible online for both masters and Ph.D. students. The research itself will allow them to improve data science skills learned in the classroom, and help us matriculate master's students to our Ph.D. program?a trend that has already started. Furthermore, a significant percentage of our student body is composed of underrepresented minorities and women. This research will help expose many of them to opportunities they would not otherwise have.